Vane seal means in rotary vane machines

ABSTRACT

The present invention is concerned with the sealing of vanes in rotary vane machines of the type in which the vanes have axial extensions which project into slots in the end walls of a rotor for guiding the vanes during radial inward and outward movement, and the outer ends of the vanes are engaged by an endless reaction surface. In accordance with the invention, a vane seal bed is formed in the radially outer portion of the vane, extending into vane extensions located in the respective slots in the end walls of the rotor. Preferably the vane seal bed is closed at its axial ends, and a vane seal means, such as a sealing strip, is mounted in the vane seal bed for slight radial movement therein for the purpose of sealing with an outer edge, the inner endless surface of the housing. The vane seal means also is in sealing contact with a longitudinal face along a wall of the vane seal bed for sealing an inter vane chamber of the vane machine while the vane seal means also extends into the vane extensions in the slots of the end walls of the rotor for the purpose of sealing also the corner between the respective rotor end wall, the endless inner housing surface, and the respective vane.

United States Eickmann atet [1 1 [451 Mar. 25, 1975 [76] Inventor: KarlEickmann, 2420 Isshiki,

Hayama-machi, Kanagawa-ken, Japan [22] Filed: Oct. 12, 1972 211 App].No: 297,256

Primary E.\'aminerC. J. Husar Assistant E.raminerLeonard Smith Attorney,Agent, or FirmMichael S. Striker [57] ABSTRACT The present invention isconcerned with the sealing of vanes in rotary vane machines of the typein which the vanes have axial extensions which project into slots in theend walls of a rotor for guiding the vanes during radial inward andoutward movement, and the outer ends of the vanes are engaged by anendless reaction surface. In accordance with the invention, a vane sealbed is formed in the radially outer portion of the vane, extending intovane extensions located in the respective slots in the end walls of therotor. Preferably the vane seal bed is closed at its axial ends, and avane seal means, such as a sealing strip, is mounted in the vane sealbed for slight radial movement therein for the purpose of sealing withan outer edge, the inner endless surface of the housing. The vane sealmeans also is in sealing contact with a longitudinal facc along a wallof the vane seal bed for sealing an inter vane chamber of the vanemachine while the vane seal means also extends into the vane extensionsin the slots of the end walls of the rotor for the purpose of sealingalso the corner between the respective rotor end wall, the endless innerhousing surface, and the respective vane 10 Claims, 25 Drawing FiguresMEANS IN ROTARY VANE MACHINES REFERENCE TO RELATED PATENTS In my US.Pat. No. 2,975,716, a vane machine, which may be a pump, motor,transmission or engine, is disclosed in which the leakage of fluidaround the ends of the vanes is prevented by providing extensions of thevanes, and slots in the rotor and walls, while the vane extensions arelocated in slots of the rotor end walls. In this manner, it has beenpossible to increase the pressure in vane machines several times, ascompared with the prior art.

Due to the extension of the vanes into the end walls of the rotor,however, a corner was formed which was not completely sealed and fromwhich fluid would escape. For the purpose of closing the unsealedcorner, my U.S. Pat. No. 3,099,964 discloses a slide element preventingleakage through the respective corner. The vane machines of my US. Pat.No. 2,975,716 and of my US. Pat. No. 3,099,964 provide a very tightsealing and a high volumetric efficiency and pressure of the machine.

However, the above-mentioned patents left some problems unsolved. Forexample, the slide element of US. Pat. No. 3,099,964 could not follownoncylindrical configurations of the endless reaction surface, so thatdead spaces could not be eliminated, which was inconvenient forcompressors, combustion engines, and gas motors since the compressionratio, volumetric efficiency, and power of the respective apparatus waslimited.

Another difficulty is that the machines of the above patent, and alsoother known vane machines, develop very high centrifugal forces actingon the vanes at a high rotary speed, so that the friction between theouter portions of the vanes or other slide elements and the endlessreaction surface becomes so great, that the parts are heated, and theefficiency of the apparatus becomes too limited for economic operation.This would, for example, take place if the rotary speed of the rotorhaving 2 to 6 inch diameters, would be increased to more than 3,000 or5,000 revolutions per minute.

SUMMARY OF THE INVENTION It is one object of the invention to overcomethe disadvantages of known vane machines and to improve rotary vanemachines to operate at high pressure tightly sealed, while the rotoroperates at a high number of revolutions, with almost no dead spacesformed.

Another object of the invention is to increase the rotary speed oftightly sealed fluid handling vane machines.

Another object of the invention is to eliminate the volume of deadspaces and thereby to increase the efficiency when handling gases andhigh pressure, for increasing the power, capacity, pressure capacity andvolumetric efficiency of machines of this type.

A further object of the invention is to eliminate or to reduce frictionbetween the outer portions of the vanes and the endless inner reactionsurface which closes the fluid handling spaces between the vanes inradially outward direction.

The main object of the invention is to make it possible to buildcompressors, combustion engines, pumps, and gas and liquid motors ofvery high volumetric capacity, rotary speed and power. In fact, due tothe in- VANE SEAL vention it becomes possible to increase the power ofgas compressors, pumps or engines to 3 HP per kilogram weight or to evenmore.

With these objects in view, the present invention provides a seal bed inthe outer edges of the vanes, and inserts a seal element radiallymovable in the seal bed so that the seal bed and the seal elementtherein extends beyond a middle portion of the rotor into axial endportions of the vane which are located in slots of the end walls of therotor.

In addition to this first embodiment of the invention, additionalembodiments and modifications of the invention may be provided. Inaccordance with another embodiment of the invention, a plurality of sealbeds and seal elements therein are provided in a single vane, or vaneassembly.

In accordance with another embodiment of the in vention a plurality ofseal beds and seal means are provided in a multiple body vanearrangement.

In accordance with another embodiment of the invention, a space isprovided between a plurality of seal beds and seal elements for fillingthe same with fluid,

or for utilizing the same as a sealing space, or as a pressure balancingspace.

In accordance with another embodiment of the invention, a straightsealing edge is provided on the outer portion of the seal element insuch an assembly that the edge seals with its middle portion abuts alongthe inner endless surface of the housing or of a closure body, whileboth ends seal and abut against the rotor end walls while being guidedin slots in the rotor end walls. In accordance with still anotherembodiment of the invention, at least one communication passage extendsfrom the seal bed to a space of the machine, which contains a fluidunder pressure.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however,

both as to its construction and its method of operation,

together with additional objects and advantages thereof, will be bestunderstood from the following detailed description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is anaxial sectional view takenon line II in FIG. 2, and illustrating an embodiment of the invention;

FIG. 2 is a cross-sectional view taken on line II-II in FIG. 1;

FIG. 3 is a longitudinal sectional view illustrating a vane according toone embodiment of the invention, and FIG. 3a is a cross-sectional viewtaken on line III- III in FIG. 3;

FIG. 4 is a longitudinal sectional view of a seal element according tothe invention, and FIG. 4a is a crosssectional view taken on line IVI\in FIG. 4',

FIG. 5 is a longitudinal sectional view illustrating a vane according toanother embodiment of the invention, provided with guide means;

FIG. 6 is a longitudinal sectional view of a vane as sembly according toanother embodiment of the invention, and FIG. 6a is a cross-sectionalview taken on line VI-VI;

FIG. 7 is a longitudinal sectional view of a vane assembly according toanother embodiment, and FIG. 7a

is a cross-sectional view taken on line VIIVII in FIG.

FIG.-8 is a longitudinal sectional view taken on line VIII-VIII in FIG.8a, and 8a is a cross-sectional view taken on line VIIIa-Vllla in FIG.8;

FIG. 9 is a longitudinal sectional view illustrating a vane assemblyaccording to another embodiment of the invention including guiderollers;

FIG. 10 is a sectional view illustrating a guide ring;

FIG. 11 is a sectional view illustrating another embodiment of a guidemeans, which can be used with the vane assembly shown in FIG. 9;

FIG. 12 is a fragmentary cross-sectional view along the line IIII inFIG. 1 but illustrating a modification of the vane assembly shown inFIGS. 13 to 18;

FIG. 13 is a longitudinal sectional view of another embodiment of thevane, and taken on line XIIIXIII in FIG. 16;

FIG. 14 is a longitudinal sectional view taken on line XIVXIV in FIG.17, and illustrating a vane assembly;

FIG. 15 is a longitudinal sectional view, illustrating anotherembodiment of the vane taken on line XVXV in FIG. 18;

FIG. 16 is a cross-sectional view taken on line XVI- XVI in FIG. 13;

FIG. 17 is a cross-sectional view taken on line XVII- XVII in FIG. 14;and

FIG. 18 is a cross-sectional exploded view taken on line XVIII-XVIII inFIG. 15;

FIG. 19 is an elevation illustrating a vane element according to theinvention; and

FIG. 20 is a cross-sectional view taken on line XX-XX in FIG. 19.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1 and2, a shaft 12 is rotatable in bearings 11 in a hollow housing 8. A rotor4 having a small diameter central or median rotor portion and end walls5 is mounted on shaft 12. Rotor 4 and its end walls 5 are provided withslots 47 extending substantially in radial direction in the rotor endwalls for guiding vanes 3 radially inward and outward.

Rotor 4 and rotor end walls 5 are preferably bolted together by bolts48. The outer and inner ends of the radial axially parallel slots 47 inthe rotor end walls are closed, while the axially extending slots inrotor 4 having only the inner ends closed. Portions on the rotor 4 andend walls 5 for closing the slots 47, reinforce the rotor means 4, 5 bybeing integral with the rotor parts between the slots 47.

A closure member 7 is partially inserted between the rotor end walls 5,and surrounds the rotor 4 with an endless inner surface 82, see FIG. 2,so that between the rotor end walls 5, the outer surface of rotor 4, andthe endless inner surface 82, and two adjacent vanes 3, intervane spacesor fluid handling chambers 17 are formed which expand and contractduring rotation of the rotor means. The radially outer ends of the vanesor vane assemblies slide along the endless inner surface 82 so that thevanes 3 move radially outward during half a revolution, and radiallyinwardly in the second half of each revolution. An inlet passage 16passes through housing 8 and closure member 7 receiving a gas or liquid,and an outlet passage 15 passes through closure member 7 and housing 8for the discharge of a fluid, which may be a liquid or gas.

Bearing means 10 are provided in housing 18 and form an axis eccentricto the axis of the rotor shaft and rotor bearings 11.

Rotary guide members 9 are carried by the bearings 10, or stationaryguide members 9 are mounted on housing 8 eccentrically to the axis ofthe shaft 12. Guide members 9 embrace guide members 19 or 39. 268, I68ofthe vanes 3 for guiding the vanes during the radial movement in therotor assembly 4, 5, 47, 48.

In the following description, reference is made to several Figuresillustrating modifications of the vanes without mentioning the numbersof the Figures, but relying on corresponding reference characters inwhich the unit order is the same to indicate corresponding parts indifferent Figures.

The vanes 3, 23, 33, 43, 53, include central portions which afterassembly in the slots 47 of the rotor means 4, 5, are located alongaxial slots of the rotor 4, with the vane end portions 94, disposed atthe ends of the central rotor portion 4. The vane end portions 94 and 95extend into the radial slots 47 in the inner faces of the rotor endwalls 5, while the central vane portions are located in the axial slots47 in the central rotor portion 4, dividing the intervane spaces orfluid handling chambers 17 from each other.

Each vane end portion 94 or 95 has radial extensions which projectradially outward beyond the central portion of the respective vane. Eachvane extension has an inner face 45, see FIG. 7, 8, 9, which embraces aguide portion of the closure member 7 for sealing purposes. The innerconfronting faces 45 are therefore perpendicular to the longitudinalfaces of the respective vanes, and the distance of the confronting innerfaces 45 from each other is substantially the same the axial length ofthe closure member 7. However, a small clearance remains, having themagnitude of a few hundredths or thousandths of a millimeter, betweenthe respective surface of closure member 7 and the respective inner face45 of the radial vane extensions so that the inner faces 45 can smoothlyand tightly sealing, slide along the end face of the closure member 7.

In order to make the manufacturing of the inner faces 45 possible, theintersecting groove 55, see FIG. 5, FIG. 8, FIG. 13, is provided betweenthe radial edges, and the central portion of the respective vane. Inthis manner, accurate grinding, pressing, or machining of the innerfaces 45 is assured.

In order to reduce the friction at the outer portions of the vanes, thevanes are guided by the guide means 9 in such a way that a smallclearance remains between the radially outer portions of the vanes, andthe endless inner surface 82 of closure member 7.

The friction between the radially outer portions of the vanes and theinner endless face 82 of closure member 7, is caused by the action ofthe centrifugal force. In order to avoid friction between the vanes andthe inner endless face 82 due to the centrifugal force, vanes, see FIGS.1, 5, 9, are provided with vane guide means 19, 39. Vane guide means 19or 39 extend from the end portions of the vane means into the annularguide ways 95 of the guide members 9 which may be provided with outerguide faces 86 for guiding the radially outer portions of the vane guidemeans 19 or 39. The guide members 9 may also be provided with innerguide faces 87 for guiding the inner portions of the vane guide means 19or 37. In order to reduce friction between the vane guide means 19 andthe guide members 9, guide shoes 168, see FIG. 11, or guide rollers 268,see FIG. 10, may be mounted on the vane guide means 19 or 39 for slidingor rolling along the guide faces 86 or 87 of the guide members 9.

According to the invention, the vane seal bed 2, 22, 32,42, 52 isprovided in the outer edge of the vane and extends from the main body ofthe respective vane into the respective end portions 94 and 95 of thevane. Furthermore, in accordance with the invention, a seal element 1,41 is inserted into the vane seal bed 2, 22, 42, 32, 52 in such a mannerthat it can slide radially therein to a limited extent.

A further specific feature of the invention resides in that the sealelement 1 or 41 has an axial extension 96 extending within the seal bed2, 22, 32, 42, 52, into the vane extensions 94 and 95. The vane sealelements of the invention may have the form of a strip, provided withbearing faces 83 along the vane seal elements 1 or 19 for supporting theseal elements 1 with the bearing faces 83 abutting the faces 92 of thevane seal bed 2, 22, 32,42, 52.

Furthermore, a seal element 1 or 41 is placed to cover the cornergrooves 55 so that the grooves 55 are closed and leakage therethrough isprevented. This is an important feature of the invention because itresults in tight sealing of the fluid handling chambers 17.

Seal elements 1 or 41 are of a much lesser weight than the weight of thevanes 3. Only the vane seal elements 1 or 41 are subjected to thecentrifugal force to slide and seal along the inner endless face 82 ofthe closure member 7. The sealing between the closure body 7 and thevane 3 is provided by the fact that outer face 81 or the edge 88, seeFIGS. 19 and 20, slides along the inner endless surface 82 of theclosure member 7 in sealing contact, while the bearing faces 83, or oneof them, lies on the respective face 92 of the vane sea] bed 2, forexample, thereby providing an exact seal.

A particularly tight seal is assured by the straight corner 88 betweenbearing face 83 and inclined outer face 89 ofthe vane seal element 1, asshown in FIGS. 19 and 20. The middle portion of the straight edge 88seals along the inner endless face 82 of closure member 7, and the endsof the straight corner 88 seal along the face portions 92 of the vaneseal bed 2, 22, 32, 42, 52, respectively, by means of the extensions 94,95 of the vanes.

Closure members 18 may be inserted into the ends of the vane seal beds2, 22, 32, 42, or 52 in order to close the vane seal beds in axialdirection. Instead of inserting a closure member 18 into the vane sealbed, it is also possible, as shown in FIGS. 9, 14 and 15, to close thevane seal bed 2,22, 32, 42, 52 by portions 56 or 57, or by otherportions of the vane extensions 94 and 95. The closing of the vane sealbeds in the vane extension in radial outward direction, may be effectedby the outer members, see FIG. 5.

In order to assist the pressing of the vane seal elements, 1, 45 againstthe inner endless face 82 of the closure member 7, and unto therespective hole surface 92 of the vane seal bed, communication passages57, see FIG. 8, may be provided at the bottom of the respective seal bedof the respective vane 3, and may extend through a portion of therespective vane in order to communicate with the respective space, whichcontains fluid, for example, within adjacent intervane space or fluidhandling chamber 17. This provides the necessary pressure of fluidagainst the vane seal element 1 or 41 in order to assure, even at lowrotary speed, a sealing contact between the vane seal element and thefaces in contact therewith.

As shown in FIGS. 8, 16, 17, and 18, it is possible to provide the vaneassembly with two vane portions 53, 54 or 303. In such an assembly it isparticularly convenient to manufacture the vane portions by simplemanufacturing operations. One or both vane portions 53 and 54 may thencontain the seal bed 52.

In the embodiment of the invention shown in FIG. 12, it is assured thatthe vane assembly 3, l, 57 can scal two adjacent fluid handling chambers17, 172, 173 which may contain fluid at different pressures. The sealingbetween two adjacent chambers 17, 172, 173 is obtained by providing twovane seal beds 2, 52 in the vanes 3, 53 or 54, and by inserting at leastone vane seal element 1 or 41 into each of the vane seal beds 2 or 52,and so forth, and providing communication passages 57 from each of theseal beds 2, 52 to the respective adjacent fluid handling chamber' 17,172, 173 which contain fluid, such as liquid or gas, under pressure.

Specific embodiments of double acting vane assemblies with a pluralityof seal means for the vane of the invention are shown in FIGS. 13 to 18.The respective parts of the vane assembly of the double acting vane typeare substantially the same and perform substantially the same functionas in the above described Figures, but the difference is that thecommunication passages 57 are extended from the different vane seal bedsin opposite directions to the respective vane portions. If vane seals ofthe type shown in FIGS. 19 and 20 are inserted in the respective sealbeds in the vanes of FIGS. 13 to 18, then the inclined faces 89 of thevane seal elements I extend toward each other so that the outer edge ofthe vane seal element 1 abuts against the wall faces 92, as shown inFIG. 18.

FIG. 18 also shows how a divided vane with two vane members 53 and 54can be utilized for a double acting vane for sealing againstcommunication with two different fluid handling spaces 17, 172. Thiseffect is achieved by inserting a plate or central plate portion 303between the other vane portions 53 and 54.

It will be understood that each of the elements described above, or twoor more together, may also find a useful application in other types ofvane seal assemblies for rotary vane machines differing from the typesdescribed above.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims.

I claim:

1. In a fluid handling device, a combination comprising a hollowhousing; a rotor mounted in said housing and including asmaller-diameter median portion and two end walls disposed at the axialends of and extending radially outwardly beyond said median portion,said rotor having substantially radially extending slots parallel withthe axis thereof and each including a central portion provided in saidmedian portion and outer portions provided in the respective end walls;a closure member provided in said housing and having an internal surfaceeccentric to said rotor and spacedly surrounding said median portionthereof, said rotor and said closure member defining an annular fluidhandling space; inlet and outlet means communicating with said space;vanes radially movably received in said slots and subdividing said spaceinto a plurality of chambers communicating seriatim with said inlet andoutlet means in response to rotation of said rotor, each of said vaneshaving an outer part including two end portions extending radiallyoutwardly beyond said internal surface, each of said outer parts beingprovided with a seal bed having ends extending to the outer portions ofthe respective slot and radially outwardly into the end portions of therespective vane and beyond said internal surface, and a seal radiallymovably received in the respective bed, said seals having end portionsextending into the ends of the respective beds and each of said sealshaving a central portion abutting against said internal surface whensaid rotor rotates to thereby seal said chambers from each other, saidend portions of said seals being free to move radially outwardly in theends of the respective seal beds so that said central portions of saidseals continue to abut against said internal surface after pronouncedwear upon said central portions of said seals as a result of abutmentagainst and sliding movement along said internal surface; andantifriction bearing means coaxial with said closure member and arrangedto hold said vanes out of frictional engagement with said internalsurface.

2. A combination as defined in claim 1, wherein said vanes furtherinclude each of said vanes further comprises corner grooves between saidmedian portion and said end portions thereof, each of said sealsextending over and sealing the corner grooves of the respective vane.

3. A combination as defined in claim 1, wherein each of said vanesincludes means for sealing the ends of the respective beds at theradially outward and axially outward sides thereof.

4. A combination as defined in claim 1, wherein each of said vanes hasat least one passage in communication with the respective bed.

5. A combination as defined in claim 1, wherein each of said vanesconsists of a plurality of portions. each of said beds being provided inat least one portion of the respective vane.

6. A combination as defined in claim 1, wherein each of said seals has astraight edge abutting against said internal surface.

7. A combination as defined in claim 6, wherein each of said sealsfurther includes an inclined outer face adjacent to said straight edgethereof.

8. A combination as defined in claim 6, wherein each of said edgesextends along the full length of the respective seal.

9. A combination as defined in claim 1, wherein each of said vanes hasan additional bed and an additional seal in said additional bed.

10. A combination as defined in claim 9, wherein each of said vanes hasat least one passage extending between said beds thereof.

1. In a fluid handling device, a combination comprising a hollowhousing; a rotor mounted in said housing and including a smallerdiametermedian portion and two end walls disposed at the axial ends of andextending radially outwardly beyond said median portion, said rotorhaving substantially radially extending slots parallel with the axisthereof and each including a central portion provided in said medianportion and outer portions provided in the respective end walls; aclosure member provided in said housing and having an internal surfaceeccentric to said rotor and spacedly surrounding said median portionthereof, said rotor and said closure member defining an annular fluidhandling space; inlet and outlet means communicating with said space;vanes radially movably received in said slots and subdividing said spaceinto a plurality of chambers communicating seriatim with said inlet andoutlet means in response to rotation of said rotor, each of said vaneshaving an outer part including two end portions extending radiallyoutwardly beyond said internal surface, each of said outer parts beingprovided with a seal bed having ends extending to the outer portions ofthe respective slot and radially outwardly into the end portions of therespective vane and beyond said internal surface, and a seal radiallymovably received in the respective bed, said seals having end portionsextending into the ends of the respective beds and each of said sealshaving a central portion abutting against said internal surface whensaid rotor rotates to thereby seal said chambers from each other, saidend portions of said seals being free to move radially outwardly in theends of the respective seal beds so that said central portions of saidseals continue to abut against said internal surface after pronouncedwear upon said central portions of said seals as a result of abutmentagainst and sliding movement along said internal surface; andantifriction bearing means coaxial with said closure member and arrangedto hold said vanes out of frictional engagement with said internalsurface.
 2. A combination as defined in claim 1, wherein said vanesfurther include each of said vanes further comprises corner groovesbetween said median portion and said end portions thereof, each of saidseals extending over and sealing the corner grooves of the respectivevane.
 3. A combination as defined in claim 1, wherein each of said vanesincludes means for sealing the ends of the respective beds at theradially outward and axially outward sides thereof.
 4. A combination asdefined in claim 1, wherein each of said vanes has at least one passagein communication with the respective bed.
 5. A combination as defined inclaim 1, wherein each of said vanes consists of a plurality of portions,each of said beds being provided in at least one portion of therespective vane.
 6. A combination as defined in claim 1, wherein each ofsaid seals has a straight edge abutting against said internal surface.7. A combination as defined in claim 6, wherein each of said sealsfurther includes an inclined outer face adjacent to said straight edgethereof.
 8. A combination as defined in claim 6, wherein each of saidedges extends along the full length of the respective seal.
 9. Acombination as defined in claim 1, wherein each of said vanes has anadditional bed and an additional seal in said additional bed.
 10. Acombination as defined in claim 9, wherein each of said vanes has atleast one passage extending between said beds thereof.